Hi Devon
First thing I would say is definitely keep your options open as much as possible, but if you can take leave then do so for as long as you can .
I went back to work when DS was 8 weeks old out of financial necessity. I work from home though so didn't have to put him in daycare, thankfully. DH didn't earn enough to even cover a baby sitter so he is home too as SAHD. It's not an idea situation, but is the best we could arrange. One thing to consider in regards to working from home is that you can't really work full time and look after you baby - it's an either or thing.
That said, a little bit of work after your baby is 6 months (or older) might be good for you - and a great opportunity potentially for your DH and mum to spend time with the little one. It's very differnt to leave your baby with someone you know loves him/her than with a childcare worker (not that they're nasty and unloving or anything, but YKWIM).
Satya - Hope you guys can work something out